To do this tutorial you need to know what a semitone is.
A major 7th is a semitone less than an octave.
- So C-B is a major 7th because B is a semitone down from C,
- and D-C# is a major 7th because C# is a semitone down from D.
Test yourself on major 7ths, focusing on the one you find hardest. For most people they’ll be the ones starting on black notes.
Sign up to my Piano Chords course to learn how to use major 7ths in context.